Understanding of neuromuscular disease is founded on careful clinical observation, electrodiagnostic studies and pathology. This protocol has been carried out to learn more about established diseases, to characterize new diseases, to assess current methodologies and technologies and to refine old methods and develop new ones. We have started a study where we try to selectively record from the 1A afferent fibers by means of a near nerve recording and mechanical tapping of the muscle. Several normal volunteers were studied and we plan to study more, as well as patients with relevant disorders. We have also studied and tried to understand a few patients with unusual disorders, such as familial hypoparathyroidism and myopathy, stiff-man syndrome, chronic fatigue syndrome, hereditary sensory motor neuropathy, hereditary liability to pressure palsies, and more.